Club,
I've had a lot of riders and customers ask me this in the last few days, and I finally found a decent article I thought would be of general interest.
Keep in mind this is not for domestic pro cyclists--they make much less. In the early 2000s I had a couple of friends making as little as $7000/year + percs for racing for some pretty well known domestic pro teams.
The article is at http://www.cyclingtips.com.au/2010/11/how-much-do-pro-cyclists-make/
Enjoy,
James T